I'm a software development engineer in Microsoft Office and have been working mostly on the RichEdit editor since 1994. In this blog I focus on mathematics in Office along with some posts on RichEdit and the early Windows days

Sans Serif Mathematical Symbols

Most mathematical documents and books use fonts with serifs, such as Times Roman. However mathematical expressions can also be displayed with sans-serif letters, such as the font this post uses. In fact, sans-serif letters are used sufficiently often in mathematical typography that six sets of them are included in the Unicode Mathematical Alphanumeric Symbols. Further rationale for these Unicode symbols is given in Section 2.2 of Unicode Technical Report #25, Unicode Support for Mathematics. People have asked how to use sans-serif variables in Microsoft Office math zones. The way to do this isn’t as simple as toggling italic on and off using the italic tool or the ctrl+i hot key. But this posts shows that it can be done.

One way any character can be entered into Word or OneNote (but not into PowerPoint, sigh) is to type the Unicode value of the character followed by the alt+x hot key as described in the post. The 52-character sans-serif upright alphabet starts at Unicode U+1D5A0, which is upper-case A. To enter A, type 1D5A0 alt+x. The lower-case letters follow the upper-case letters, so the lower-case a has the code U+1D5BA. This can be entered by typing 1D5BA alt+x. The 52-character sans-serif bold, italic, and bold-italic sets follow the upright set and start at U+1D5D4, U+1D608, and U+1D63C, respectively. In addition there are bold and bold-italic Greek sets, which start at U+1D756 and U+1D790, respectively.

Entering symbols using alt+x is useful, but if you want to enter lots of symbols, it’s not very convenient. Clearly it would be nice to have a sans-serif button on the math ribbon to toggle between sans serif and serif letters. In this connection, it would also be handy to have bold and italic buttons on the math ribbon, but currently they’re only available on the Home ribbon. Another way to enter sans-serif letters does exist: add the letters you need to math autocorrect.

To add an AutoCorrect entry for any Unicode character, go to the AutoCorrect dialog (the math AutoCorrect dialog for entries into math zones), and in the Replace text box type the AutoCorrect name you want to use and in the With text box type the Unicode hex code of the desired character followed by alt+x. The method works the same way as using alt+x directly in the document, except that you assign a simple string to enter the character instead of entering the character into the document. For example, you could assign the string “\A” to enter U+1D5A0, that is, to enter upper-case sans-serif A. It doesn’t take long to add such strings for all 52 letters in a sans-serif alphabet. (The reason this works for entering math autocorrect symbols is because the text boxes are RichEdit controls, which support alt+x). You can add math autocorrect entries using any Office application that supports math zones and the entries are shared by all Office applications.

If sans-serif italic letters are what you need the most, you might want to use “\A”, etc., for them and use some longer name for the upright characters, such as “\uA”. Note that once you’ve entered a sans-serif letter, you can change its bold and italic properties by selecting the character and using the bold and italic hot keys and buttons.

FremyCompany, what sort of operators have serifs? Numbers, I’d understand, and integral signs…. What you’re asking for is a different font.

Trouble is, there are only a handful of OpenType Math fonts: Cambria Math, Asana Math, Neo Euler, Latin Modern Math, and XITS (repackaged STIX); Lucida Math and Tiro’s Maxwell are works-in-progress. None of these are sans-serif in style.

This post points out that sans-serif English letters are built into a Unicode math font by design. You don't need a "sans-serif" math font, except perhaps for integrals and summations. I'd much prefer to have a "sans-serif" OpenType feature that exposes sans-serif integrals and summations to having a so-called "sans-serif" Unicode font. The latter would break the intention of the Unicode math alphanumerics. In particular, it'd be most unfortunate to put sans-serif characters in the ASCII and U+1D400..1D49B code points of a Unicode math font.

Still, it would be nice to have a smoother way to access sans-serif characters than the methods given in this blog post. As the expression goes, Rome wasn't built in a day and I for one had no idea that sans-serif math would be so popular. Literally none of my myriad math and physics text books have sans-serif letters except for very special purposes. But times change and we need to make it easy to use sans-serif letters.

Consider a text written in Calibri or Corbel with mathematical bits: would the serifs of Cambria Math be a good fit? True, this would be less-than-ideal typographically, and tensors (e.g.) couldn’t be distinguished by the use of sans-serif; but I think there is room for a full sans-serif math font.

(Or we could deliberately not make a math sans font, and therefore encourage mathematical writing to eschew sans text as well; I’d agree with that strategy. ☺)